Save jpg-images for detector demo if used flag: -prefix <filename>

AlexeyAB

2018-05-21 b88b7b645bc71ddcd83f81744c78419e0ed15078

 src/demo.c

@@ -243,7 +243,8 @@
            }
            }else{
                char buff[256];
                sprintf(buff, "%s_%08d", prefix, count);
                sprintf(buff, "%s_%08d.jpg", prefix, count);
            cvSaveImage(buff, show_img, 0);
                //save_image(disp, buff);
            }